[IC] Kishsaver Feet

[wcass]

A part of my Kishsaver that is not in great condition is the feet.  On my KS, the two front feet are OK, but the back two are deformed - squashed flat. I think that the keyboard might have been riveted into a keyboard tray. Anyway, I was thinking about casting new feet.

I have lots of choices for mold making - the cheap stuff makes lower detail castings and is only good for very few castings - expensive molds usually last longer and have better detail. So, I need to know if I will be making feet for just myself, or for the whole lot of you guys with Kishsavers. My goal is to keep the cost under $10 to replace all 4. I may need help modeling this, so if you have the skill and software, let me know.

The shape of the feet is like a rectangular grommet - 9mm x 9mm.

[CPTBadAss]

I'd be interested.

[jwaz]

I'd be interested.

+1

[riotonthebay]

I'd be interested.

+1

+1

[HPE1000]

I'd be down, I still need to convert it and powder coat it but this is cheap so I am okay with that

[sleepy916]

In.

[Parak]

Make them EPDM and I'm in

[wcass]

Make them EPDM and I'm in

I hadn't considered EPDM. What about that material makes you want to use it? It might work if the formulation was in the lower half of it's Shore range. Anything over 65A might be too hard.

[Parak]

Make them EPDM and I'm in

I hadn't considered EPDM. What about that material makes you want to use it? It might work if the formulation was in the lower half of it's Shore range. Anything over 65A might be too hard.

Mainly the wear resistance and longevity. But depends on the cost I suppose - too much and it's not worth it.

[HoffmanMyster]

I'd be interested.

+1

+1

+1

[rindorbrot]

I'd be in for a set, too.

[vivalarevolución]

interested here.

[Game Theory]

Also interested in a set!

Hope you don't mind but I posted a link to this IC in the Deskthority forum. http://deskthority.net/marketplace-f11/kishsaver-replacement-feet-interest-check-on-geekhack-t8050.html

[mashby]

I'm in as well.

[Techno Trousers]

I'm in.

[snoopy]

I'm interested in a set or two...

[jdcarpe]

I'd buy a set of these

[Monster-Toys]

In, too. 

[wcass]

OK, thanks to Monster-Toys we have two mold designs; a classic 2 piece, clam shell, top pour and a 3 piece injection mold type. The three piece has the advantage of no mold seams on the foot bottom. The two piece uses less mold material and less voids, so it would cost less to have made.


For the actual foot material, I would like to use platinum cure silicone. It is chemical, UV, and heat resistant and should last for many years. It can be formulated to a specific color and Shore hardness, but it is more expensive than other materials and usually requires vacuum degassing. An inexpensive alternative might be Oogoo.

As this is all very much new and untested, I think I will start out going the inexpensive route and reporting back what works and what doesn't. I think I will also look into making those plastic spacer things that always seem to be broken.

[Techno Trousers]

Nice! I look forward to seeing how these projects progress.

[orihalcon]

Do you actually have an injection molding machine, or would you have a company make them for you?  ...Or are the molds low pressure where you can just squeeze silicone into them by hand?  Looks like a great project! I'd be interested in some if I can find a Kishsaver to put them on!

[wcass]

The plastic spacer thingies turned out great. The feet, not so great.

The feet tops fit in the case holes, but not as tight as the original. The edges are not nice and sharp (like the original) and my Oogoo feels a bit too squishy - like i might have stirred it too vigorously and introduced some small bubbles. I aslo think that the silicone shrank - perhaps as much as 10%. 

But i learned a lot.

[sleepy916]

The plastic spacer thingies turned out great. The feet, not so great.

The feet tops fit in the case holes, but not as tight as the original. The edges are not nice and sharp (like the original) and my Oogoo feels a bit too squishy - like i might have stirred it too vigorously and introduced some small bubbles. I aslo think that the silicone shrank - perhaps as much as 10%. 

But i learned a lot.

That is too bad about the feet but at least the spacers worked out.

[vivalarevolución]

The plastic spacer thingies turned out great. The feet, not so great.

The feet tops fit in the case holes, but not as tight as the original. The edges are not nice and sharp (like the original) and my Oogoo feels a bit too squishy - like i might have stirred it too vigorously and introduced some small bubbles. I aslo think that the silicone shrank - perhaps as much as 10%. 

But i learned a lot.

So did you just use silicone clay for the feet, rather than attempted to 3D print anything?

[wcass]

So did you just use silicone clay for the feet, rather than attempted to 3D print anything?

I 3D printed a mold for the feet. I used Oogoo to fill the mold. Oogoo does not pour so I just crammed as much in as I could with a Popsicle stick. Some of the feet had signs of trapped air pockets. I'm not sure how to avoid that with something so viscous. I'll post pictures as soon as i find them.

[vivalarevolución]

So did you just use silicone clay for the feet, rather than attempted to 3D print anything?

I 3D printed a mold for the feet. I used Oogoo to fill the mold. Oogoo does not pour so I just crammed as much in as I could with a Popsicle stick. Some of the feet had signs of trapped air pockets. I'm not sure how to avoid that with something so viscous. I'll post pictures as soon as i find them.

Was there any preparation after you filled the molds, or does that substance just have to sit and harden?

[REVENGE]

Nice one wcass, in for two sets when this is complete!

[wcass]

I applied a very thin coat of wax on the mold to smooth the texture and as a mold release. That was probably not necessary.

It might have helped if I had degassed the Oogoo prior to casting, but I don't have a vacuum chamber. I demolded at about 4 hours. Oogoo is very interesting stuff and only costs about $5 at local grocer/hardware store vs $30 for Oomoo available on-line.

[The_Beast]

This reminds me of some double glazing gaskets when I worked for a curtainwall window company. I use to have to count the linear feet of gasket needed for entire buildings/skyscrapers

This might work if you stuff something in the bulb since it more than likely has a pretty low durometer

[vivalarevolución]

I applied a very thin coat of wax on the mold to smooth the texture and as a mold release. That was probably not necessary.

It might have helped if I had degassed the Oogoo prior to casting, but I don't have a vacuum chamber. I demolded at about 4 hours. Oogoo is very interesting stuff and only costs about $5 at local grocer/hardware store vs $30 for Oomoo available on-line.
(Attachment Link)

Did you experiment with Sugru?  If so, how did it compare?  I'm not really sure if Oogoo and Sugru are in the same class of materials or uses.

[lot_lizard]

I realize in advance that I am resurrecting an ancient topic/thread, but it was valuable to me recently when exploring options for the Kishsaver's feet, and this was the only thread really dedicated to the concept.  Here is a link the 3d printing option if interested:  https://geekhack.org/index.php?topic=52394.msg2068178#msg2068178